The present invention is directed to a ventilating system connector assembly, and particularly, to a two part assembly that permits a rapid and simple connection between a secondary duct and a main duct.
In the prior art, various connectors have been proposed in the field of heating, ventilating and air conditioning (HVAC) systems in order to tap into a main plenum or duct of a ventilating system. Typically, an opening is made in the main duct, and a take-off pipe or pipe assembly is attached to the opening. The pipe or assembly allows a secondary duct to be attached to the main duct.
In U.S. Pat. No. 482,808, to McGoron, the take-off pipe employs a fixed collar on one end with bendable flanges on the other end for attachment to the main flue.
U.S. Pat. No. 3,477,745 to Williams et al. discloses a quick connection between a take-off pipe and a duct panel. The quick connection is attained by including a cutter on the take-off pipe that cuts a hole in the duct panel. A helical retainer member having one end free of the pipe follows the cutter through the panel to the opposite side thereby securing the take-off pipe to the panel.
U.S. Pat. No. 5,538,293 to Kolt describes a method for installing a secondary duct to a main duct. In one embodiment, a tapered take-off pipe employs a number of outwardly extending resilient lanced projections. The projections are initially pressed inward when the take-off pipe is inserted into an opening made in the main duct. After passing the opening, the projections snap outwardly to prevent subsequent removal of the take-off pipe.
While a number of different ways have been proposed to attach a take-off pipe to a main duct or panel, a number of disadvantages remain. The method of Kolt requires a tapered shape and projections to give a tight fit, and is susceptible to leaking over time. The Williams method requires that the take-off pipe be made with a cutter. Often times, installers are left with conventional take-off pipes and must perform cutting, hand fitting, tapping, sealing and other time consuming steps to attach the pipe to a main duct or pane.
Accordingly, a need exists for improved methods and designs to attach a secondary duct to a main duct using a take-off pipe or pipe assembly. The present invention responds to this need by providing a connector assembly and method of use which allows for rapid and efficient attachment and removal of secondary ducts to main ducts.
Accordingly, it is a first object of the present invention to provide a connector assembly for attaching a secondary duct to a main duct.
Another object of the present invention is a method of attaching a secondary duct to a main duct using a connector assembly employing a two piece design.
A still further object of the invention is a connector assembly for HVAC application comprising a take-off pipe and a collar, the take-off pipe designed to easily attach to a main duct, and further connect to the collar to facilitate attachment of a secondary duct to the main duct.
Other objects and advantages of the present invention will become apparent as a description thereof proceeds.
In satisfaction of the foregoing objects and advantages, the present invention is an improvement in connectors for HVAC systems whereby a secondary duct is to be connected to a main duct. The inventive ventilating system connector assembly comprises a take-off pipe having a generally cylindrical body with at least one resilient tab extending outwardly from the body. The body also has at least one set of grooves in a body wall. The assembly also includes a generally cylindrical collar sized to mate with the body of the takeoff pipe, the collar having at least one protrusion extending outwardly from the collar. The protrusion is adapted to engage the at least one groove of the groove set to attach the collar to the take-off pipe in a first position, and be circumferentially spaced from the groove set in a second position.
The take-off pipe body can have a plurality of spaced apart grooved wall segments and a plurality of spaced apart tabs, and the collar can have a plurality of the spaced apart protrusions. Each protrusion is spaced apart on the collar to engage respective grooves of the wall segments when the collar is mated with the body. The resilient tabs can be equally spaced apart with the grooved wall segments being positioned between adjacent resilient tabs. The grooves of each wall segment extend along a circumferential path for a defined distance, and are aligned longitudinally along the wall segment.
The collar can have an attachment flange surrounding one end thereof with a plurality of spaced apart openings to receive fasteners for attachment to the main duct.
The invention also includes a method of attaching the take-off pipe and collar connector assembly to a main duct. The method entails first making an opening in a portion of the main duct using conventional means. Then, one end of the take-off pipe is inserted into the opening, the tabs being depressing by reason of their resiliency. Once the edge of the tab passes through the opening, the tab then extends outwardly, thus securing the takeoff pipe end into the opening. The cylindrical collar is mated with the take-off pipe extending from the main duct such that the protrusions thereon engage a groove in the body wall to attach the collar to the take-off pipe. The collar can have an attachment flange to facilitate fastening to the main duct using adhesives, fasteners, a combination of both, or the like. A secondary duct can then be secured to the assembly in conventional fashion.
For removal, the cylindrical collar is rotated to disengage the protrusions from the grooves so that the collar can be removed from the take-off pipe.